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A licensee is trying to use Distribution Float Particle Parameters for the Noise properties of a Beam Particle. When trying to change these parameters in a Blueprint, some work, others don't.
When ejecting to Simulate mode and checking the details of the Particle System, the blueprint is changing the parameter values, but the changes aren't reflected in the visuals.
*Sample map & screen shots attached. Repro steps below
1. Open attached project file.
2. Open NewMap. A BP with Particle System is in the map. (Attached screenshots show particle settings and use of Distribution Float Particle Parameters)
3. Play the map and use the following keys to change parameters
-1 key = change curve to smooth
-2 key = change curve to sharp points
-3 key = Make vertical range of noise smaller
-4 key = Make vertical range of noise bigger
*Keys 3 & 4 change the parameter and the vertical height of the noise changes accordingly.
*Keys 1 and 2 change the parameter, but the noise doesn't change. However, changing the same parameter in Cascade causes the noise to be either smooth or jagged.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-21872 in the post.